JPH0423703Y2 - - Google Patents

Description

[Detailed explanation of the idea]

FIELD OF INDUSTRIAL APPLICATION This invention relates to an improvement of a seat configured so that its longitudinal position can be adjusted by a longitudinal position adjustment mechanism.

[Conventional technology]

For example, the front seat of a car has a built-in seat track, which is a front-rear position adjustment mechanism for adjusting the front and rear positions of the seat. It allows you to take a seated position.
The seat track includes a lower rail that is fixed to the vehicle floor, and an upper rail that supports the seat and is slidably supported by the lower rail in the longitudinal direction.
By unlocking the seat track,
It is configured so that the front and back position of the seat can be adjusted by sliding the top rail in the front and back direction. The upper rail and the lower rail, which are the main constituent members of the seat track, are generally assembled so as to be relatively slidable by the following assembly structure. As shown in FIG. 4, the top rail 3 includes a flat top wall 3a, side walls 3b hanging down from both ends of the top wall 3a, and bending from the bottom end of the side wall 3b. A pair of rolling element receiving walls 3c, 3 which extend inwardly and face each other with a certain distance between them.
It is equipped with c. On the other hand, lower rail 2
has a substantially inverted hat shape in cross section, and includes a lower wall portion 2a that faces the upper wall portion 3a of the upper rail 3 and has a width smaller than the distance between the pair of rolling element receiving walls 3c, 3c; Each side wall portion 2b extends upward from both ends of the portion 2a, and the side wall portion 2b bends from the upper end and extends outward, and faces the pair of rolling element receiving walls 3c, 3c of the upper rail 3. A pair of rolling element receiving walls 2c, 2c are provided.
Then, the upper rail 3 is assembled to the lower rail 2 fixed to the floor by inserting the lower rail 2 into the upper rail 3. During this assembly, the roller 13 held by the retainer 12 and a pair of ball groups 14 located on both sides of the roller 13 are interposed between the upper rail 3 and the lower rail 2. There is. The rollers 13 are interposed at at least two locations spaced apart from each other by a predetermined distance in the front-rear direction. Then, the upper wall portion 3a of the Atsupa rail 3 and the lower rail 2
The roller 13 disposed between the lower wall portion 2a of
and each of the above-mentioned rolling element receiving walls 3c, 3 of the Atsupara rail 3.
c and each of the rolling element receiving walls 2c, 2c of the lower rail 2.
Each of the above-mentioned ball groups 14 respectively arranged between
..., 14..., the upper rail 3 is slidably supported by the lower rail 2. That is, the upper rail 3 is
As the ball 14 rolls, it slides on the lower rail 2. In this case, roller 13
The distance between the rolling axis (rotation center) of the roller 13 and the contact area between the roller 13 and the upper rail 3 (the lower surface of the upper wall 3a) is the distance between the rolling axis of the roller 13 and the roller 1
3 and the contact portion of the lower rail 2 (upper surface of the lower wall portion 2a), the amount of movement of the upper rail 3 with respect to the lower rail 2 is always twice the amount of movement of the rollers 13 with respect to the lower rail 2. .

[Problem that the invention attempts to solve]

Incidentally, recently, there has been an increasing demand for expanding the sliding range of the seat in order to expand the adjustment range of the front and rear positions of the seat so that the driver can take a more optimal driving position. There is. However, with the conventional seat track structure, when attempting to expand the sliding range of the seat, the following problems arise, and the sliding range cannot be increased significantly. That is, as mentioned above, since the ratio (2:1) between the amount of movement of the upper rail 3 and the amount of movement of the rollers 13 is fixed, when increasing the sliding range of the seat, that is, the amount of sliding of the upper rail 3, the lower rail Naturally, the amount of rolling movement of the rollers 13 rolling on the rails 2 also increases, and the rollers 13 are disposed at at least two locations between the rails 2 and 3 at a predetermined interval in the rail length direction. Therefore, when increasing the sliding range of the seat, the rail length of the lower rail 2 must also be increased. However, when the rail length of the lower rail 2 is increased in this way, when the seat is positioned forward, the lower rail 2 becomes a protrusion.
The rear part of the vehicle protrudes from the seat and is exposed inside the vehicle. In such a case, not only will the aesthetics of the interior of the vehicle be impaired, but the danger in an emergency will inevitably increase.Especially, front seats equipped with a walk-in mechanism in two-door cars, etc. Since a large amount of sheet sliding is required, the above-mentioned disadvantages were noticeable. This invention was devised under the above-mentioned circumstances, and includes a lower rail fixed to the floor,
The seat is configured such that the longitudinal position can be adjusted by a longitudinal position adjustment mechanism including an upper rail slidably supported by the lower rail while supporting the seat, without increasing the rail length of the lower rail. The object of the present invention is to provide a seat configured to increase the slide adjustment range of the seat.

[Means to solve the problem]

In order to solve the above problem, the sheet of this invention is
The seat is configured so that its longitudinal position can be adjusted by a longitudinal position adjustment mechanism that includes a lower rail fixed to the floor and an upper rail that supports the seat and is slidably supported by the lower rail. Between the lower rail and the upper rail, there is a small diameter part that contacts the rolling surface on the lower rail side, and a small diameter part that has the same axis as the small diameter part and has a larger diameter than the small diameter part and has a diameter on the upper rail side. A plurality of rolling elements each having a large diameter portion that comes into contact with the rolling surface of the rail are interposed therebetween, and a notch is further formed between the lower rail and the upper rail to accommodate each of the plurality of rolling elements. The present invention is characterized in that a retainer is interposed therebetween, and a slide piece portion is integrally formed on the retainer to slide into contact with both the lower rail and the upper rail to define the distance between them.

[Action and effect]

The upper rail that supports the seat is supported by the lower rail via rolling elements, and slides against the lower rail by the rolling of the rolling elements. The large diameter portion is in contact with the rolling surface on the upper rail side. That is, when the upper rail slides with respect to the lower rail, the large diameter portion of the rolling element rolls relative to the rolling surface of the upper rail, while the small diameter portion of the rolling element rolls on the rolling surface of the lower rail. Therefore,
The distance between the rolling axis of the rolling element (rotating axis) and the contact area between the rolling element and the lower rail shall be smaller than the distance between the rolling axis of the rolling element and the contact area between the rolling element and the upper rail. Therefore, the amount of slide of the upper rail relative to the lower rail is at least twice the distance traveled by the rolling element relative to the lower rail, and the ratio of the amount of movement between the upper rail and the rolling element is greater than the distance the rolling element moves relative to the lower rail. It can be freely changed by changing the ratio of the diameters of the parts. In other words, if the diameter of the small diameter part is a and the diameter of the large diameter part is 2a, the amount of slide of the upper rail will be three times the amount of movement of the rolling element (a + 2a/a =), but the diameter of the large diameter part will be 2a. If the diameter is further increased to 3a, the sliding amount of the upper rail will be (a+3a/a=) four times the moving amount of the rolling element. In other words, it is possible to increase the amount of slide of the upper rail relative to the lower rail while keeping the amount of movement of the rolling elements constant. Further, by reducing the diameter of the small diameter portion and leaving the diameter of the large diameter portion unchanged or increasing it, the sliding amount of the upper rail can be kept constant or increased while reducing the amount of movement of the rolling elements. In this way, with the seat of the present invention, even if the sliding amount of the top rail with respect to the lower rail is increased, the travel distance of the rolling elements rolling on the lower rail can be kept constant or reduced, so the adjustment range of the seat's front and rear slides can be expanded. Even if
There is no need to set a long rail length for the lower rail, and it can also be shortened. As a result, if the automobile seat mentioned above as a conventional example is configured with the seat of the present invention, the adjustment range of the seat can be expanded without the problems seen in the conventional example. This allows the driver to take an optimal seat position. Moreover, in the present invention, a retainer is interposed between the lower rail and the upper rail, and the retainer is provided with a notch for accommodating a plurality of rolling elements, and this retainer is in sliding contact with both the lower rail and the upper rail. Since the slide piece part that defines the interval between them is integrally formed, even when the upper rail and the lower rail move relative to each other, the plurality of rolling elements are always maintained at a predetermined interval by the retainer. Therefore, the relative movement between the upper rail and the lower rail is highly stable. Furthermore, since the slide piece portion described above is integrally formed with this retainer, the distance between the upper rail and the lower rail can be stably maintained even in areas other than the portion where the plurality of rolling elements are present. This prevents rattling between the upper rail and the lower rail during sliding. Since the slide piece portion is integrally formed with the retainer, it is possible to suppress an increase in the number of parts and reduce costs, and it is also possible to improve the workability of assembly.

[Explanation of Examples]

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3. Note that members equivalent to those in the conventional example are given the same reference numerals. This example shows a case in which the present invention is applied to an automobile seat that is equipped with a seat track 1 that is a longitudinal adjustment mechanism and is configured such that its longitudinal position can be adjusted by the seat track 1. As shown in FIG. 3, an automobile seat includes a lower rail 2 having a predetermined rail length fixed to the vehicle floor via seat legs 10, and a lower rail 2 having a predetermined rail length.
The seat track 1 is provided with an upper rail 3 that is slidably supported by the upper rail 3, and is disposed on both sides of the seat, and a seat cushion frame 11 is fixed to the upper surface of each of the upper rails 3, 3. . Further, in this example, the lower rail 2 and the upper rail 3 are conventional and common ones. That is, Figures 1 and 3
As shown in the figure, the lower rail 2 includes a flat lower wall portion 2a, side wall portions 2b, 2b extending upward from both ends of the lower wall portion 2a, and side wall portions 2b, 2b.
It is provided with a pair of rolling pair receiving walls 2c, 2c which are bent and extend outward from the upper end of the roller. On the other hand, the upper rail 3 includes a flat upper wall portion 3a facing the lower wall portion 2a of the lower rail 2, side wall portions 3b, 3b bent and hanging down from both ends of the upper wall portion 3a, and this side wall portion. The rolling element receiving walls 2c of the lower rail 2 are bent inward from the lower ends of the lower rails 3b, 3b, and are opposed to each other with a distance larger than the distance between the respective side wall portions 2b, 2b of the lower rail 2.
A pair of rolling element receiving walls 3c, 3c are provided at a lower position and vertically opposed to this. By operating the operating lever 5 of the lock mechanism 4 built into the seat track 1, it is possible to select between a state in which the seat can be freely slid and a state in which the seat is prohibited from sliding. . In this example, the following rolling elements 6 are interposed between the lower rail 2 and the upper rail 3, so that the upper rail 3 is slidably supported by the lower rail 2. Figures 1 and 2
As shown in the figure, the rolling elements 6 are connected to the lower rail 2.
A substantially cylindrical large-diameter portion 7 whose outer circumferential surface contacts the rolling surface 3d set on the lower surface of the upper wall portion 3a of the upper rail 3 while entering between the respective side wall portions 2b, 2b.
The rolling surface 2d, which is integrally formed with the same axis on both sides of the large diameter part 7 and set on the upper surface of the rolling element receiving wall 2c of the lower rail 2, has a diameter smaller than that of the large diameter part 7. It is provided with a pair of substantially cylindrical small diameter portions 8, 8 whose outer peripheral surfaces are in contact with each other. And this rolling element 6
are held by a retainer 9 interposed between both rails 2 and 3, and are arranged at two locations in the rail length direction at a predetermined interval. In this example, the retainer 9 is formed by resin molding to have substantially the same cross-sectional shape as the upper rail 3, and the upper wall portion 3a has a rectangular notch 9.
b are established at two locations separated by a predetermined interval. The large diameter portions 7, 7 of the pair of rolling elements 6, 6 are exposed to the rolling surface 3d of the upper rail 3 from the respective notches 9b, 9b, and the large diameter portions 7, 7 are connected to the notches 9b. Due to the engagement of the retainer 9
is pulled by the rolling elements 6 and moved together with the rolling elements 6, and the rolling elements 6 are restrained so that the distance between the rolling elements 6, 6 is always maintained at a predetermined interval. Furthermore, this retainer 9 includes a lower rail 2.
A pair of slide piece parts 9c, 9c are provided which fit between the rolling element receiving wall 2c on the side and the rolling element receiving wall 3c on the upper rail 3 side, and are formed with both upper and lower surfaces as sliding surfaces 9d. The piece parts 9c, 9c prevent the upper rail 3 and the lower rail 2 from shaking during sliding. Note that the rolling element receiving wall 2c on the lower rail 2 side
A ball may be interposed between the upper rail 3 and the rolling element receiving wall 3c, and the ball may be held by the spacer member 9. In the seat of this example configured as described above, the sliding movement of the seat is performed through the sliding movement of the upper rail 3 with respect to the lower rail 2, but as described above, the upper rail 3 moves the rolling elements 6. Since the upper rail 3 is supported by the lower rail 2 through the upper rail 3, the upper rail 3 slides relative to the lower rail 2 due to the rolling of the rolling elements 6. In this case, the small diameter portion 8 of the rolling element 6 is on the rolling surface 2d of the lower rail side 2, and the small diameter portion 8 of the rolling element 6 is on the upper rail 3.
The large diameter portions 7 are in contact with the side rolling surfaces 3d, and the distance between the rolling axis of the rolling elements 6 and the rolling contact area between the rolling elements 6 and the lower rail 2 is equal to the rolling axis of the rolling elements 6. The distance between the core and the rolling contact portion between the rolling elements 6 and the upper rail 3 is smaller than the distance. Therefore, lower rail 2 of Atsupa rail 3
The amount of sliding relative to the lower rail 2 of the rolling element 6 is
However, by changing the ratio of the diameters of the large diameter portion 7 and the small diameter portion 8 of the rolling element 6, the ratio of the amount of movement of both of them relative to the lower rail 2 can be changed arbitrarily. It can be changed.
For example, if the diameter of the small diameter portion 8 is left as is and the diameter of the large diameter portion 7 is further increased, while the amount of movement of the rolling elements 6 relative to the lower rail 2 is kept constant, only the amount by which the upper rail 3, that is, the seat slides relative to the lower rail 2, is increased. can be increased. Furthermore, by reducing the diameter of the small diameter portion 8 and leaving the diameter of the large diameter portion 7 unchanged or increasing it, the amount of sliding of the upper rail 3 can be kept constant or increased while reducing the amount of movement of the rolling elements 6. can. That is, in the seat of this example, the amount of sliding of the upper rail 3 can be increased while the amount of movement of the rolling elements 6 rolling on the lower rail 2 is kept small or constant. Therefore, lower rail 2
It is possible to expand the slide adjustment range of the seat while setting the rail length short, and it is possible to completely eliminate the disadvantages that occur when increasing the amount of seat slide as in the conventional example. The scope of the present invention is not limited to the above-mentioned embodiments. For example, the structure of the rolling elements can be modified in various ways other than the above-mentioned embodiments, and the structure of the lower rail and the upper rail may also be modified in accordance with the above-mentioned embodiments. It is not limited to the examples.

[Brief explanation of drawings]

Fig. 1 is an enlarged cross-sectional view taken along the - line in Fig. 3, Fig. 2 is a perspective view of a rolling element according to an embodiment of the present invention, and Fig. 3 shows a state in which the longitudinal position adjustment mechanism according to the embodiment is removed from the seat. The perspective view shown in FIG. 4 is a sectional view of a conventional example. 1... Front-rear position adjustment mechanism (seat track),
2... Lower rail, 2d... Rolling surface, 3... Upper rail, 3d... Rolling surface, 6... Rolling element, 7...
...Large diameter part, 8...Small diameter part, 9...Spacer, 9b
...Notch part (of the spacer), 9c...Slide piece part (of the spacer).

Claims (1)

[Claims for Utility Model Registration] The longitudinal position can be adjusted by a longitudinal position adjustment mechanism that includes a lower rail fixed to the floor and an upper rail that supports the seat and is slidably supported by the lower rail. A seat configured as such, wherein the lower rail and the upper rail have a small diameter portion that contacts the rolling surface on the lower rail side, and a seat that has the same axis as the small diameter portion and is larger than the small diameter portion. A plurality of rolling elements having a large diameter portion that contacts the rolling surface on the upper rail side are interposed, and each of the plurality of rolling elements is further interposed between the lower rail and the upper rail. A retainer having a notch for accommodating the slide piece is interposed therebetween, and a slide piece part is integrally formed on the retainer to slide into contact with both the lower rail and the upper rail to define the distance between them. sheet.